1. Field of the Invention
This invention relates to a process for making a medical glove whose fingers have thinner walls than the rest of the glove.
2. Description of the Related Art
Manufacturing surgical gloves involves a process that includes dipping a form fashioned to resemble the human hand into a solution of coagulant, drying the coagulant and then immersing the form into an elastomeric (e.g., latex) compound. After depositing the layer of latex compound on the form, the forms are usually rotated continuously until the coagulant reacts producing a gelled latex film. This rotation equalizes any wet latex runs and assures a more uniform overall gauge in the finished gloves. After the film is gelled, it is leached with water in order to remove any water soluble materials from the deposited film, dried, vulcanized and stripped from the glove form resulting in a finished glove. The above process involves dipping the glove form into a latex compound fingertips first; thus the fingertips are the last to be pulled out of the latex compound. Therefore, the fingertip gauge of the glove produced with the above process must be heavier than or equal to the cuff gauge. To prevent cuff tears during donning, the cuff gauge of a glove is generally at least 0.15 mm. Consequently, the fingertip gauge must be equal to or thicker than 0.15 mm. By these standards, current gloves are not suitable for delicate operations, such as those performed by ophthalmologists, due to poor touch sensitivity. Various methods have been proposed to produce gloves in which the fingertip gauge is thinner than the cuff gauge.
U.S. Pat. No. 2,097,528, issued on Nov. 2, 1937, to H. A. Morton, discloses a method of making rubber gloves in which a glove form is first immersed in a coagulant solution to provide a uniform coating over the form. The form is then dipped into a neutralizing agent, fingers first, to a depth that corresponds to the portion of the glove on which a thinner deposit is desired. Neutralizing the coagulant reduces its effectiveness; thus, when the form is subsequently submerged in a latex dispersion, less latex is deposited on the neutralized coagulant and the resultant glove is thinner there. A similar result is achieved in a process in which the form is dipped in a latex solution two (or more) times, with a portion of the form being dipped into a neutralizing solution between latex immersions.
U.S. Pat. No. 3,397,265, issued on Aug. 13, 1968, to H. N. Ansell, discloses a process in which a glove form that is coated with a concentrated coagulant is immersed in a solvent for the coagulant to a depth that corresponds to the portion of the form on which a thin latex coating is ultimately desired. After removing the coagulant coating from that portion of the form, the form is dipped into a dilute coagulant, so that the dilute coagulant covers the portion of the form from which the concentrated coagulant had been removed. Finally, the form is immersed in a latex solution. More latex deposits on the portion of the form that is coated with concentrated coagulant than on the portion coated with dilute coagulant. Consequently, the resultant glove is thicker in the region of the cuff than in the fingers.
U.S. Pat. No. 3,859,410, issued on Jan. 7, 1975, to H. Sidley, discloses a method of reproducing a glove having relatively thin wall thickness in the finger and palm portions and thicker wall thickness in the cuff region by first spraying concentrated coagulant onto the cuff region of a form and dilute coagulant onto the fingers and palm. The form is then dipped in a latex solution, where a thicker latex coating deposits on the region coated with concentrated coagulant.
Each of the procedures of the prior art permit the fabrication of gloves having less thickness in the fingers than the cuff, but they involve the use of corrosive solvents and/or are unsuited for fabricating gloves having fingers of extremely thin (thickness &lt;0.13 mm) wall thickness.